Multi-acre shub-like corpse, summoned in a cataclysmic war and slain almost immediately. Didn't decay though (that is not dead which can eternal lie) and starving peasants in the vicinity turned to it as a food source during the famine filled dark ages that followed. Teratagenic effects of this diet have made the local population . . . interesting.

Even after a couple hundred years there's still plenty left though. Care for a bite?